1. Field of the Invention
This invention relates to a tool for applying a mounting bracket for an automotive rear view mirror to a windshield. More particularly, this invention relates to a rework tool for applying and bonding a metal mounting bracket for a rear view mirror to a glass windshield using a heat curable adhesive.
2. Background Information
One method for installing rear view mirrors in automotive vehicles is by securing the base of the mirror by mechanical means such as a set screw to a metal mounting bracket. The bracket is, in turn, secured to the windshield of the vehicle by means of an adhesive.
During the life of the vehicle the adhesive forming the bond between the mounting bracket and the glass may weaken sufficiently that it will no longer support the weight of the mirror, resulting in the mirror and the associated mounting bracket becoming detached from the windshield. In some instances it may become desirable to change the location of the mounting bracket.
There are available in the market place liquid adhesives, particularly those based on cyanoacrylates, that cure rapidly under ambient conditions. These adhesives are used to reartach the mounting bracket to the windshield, however the durability of the resulting bond under the conditions encountered during operation of the vehicle may be less than can be achieved using the heat curable adhesives that are used to initially bond the mounting bracket to the windshield.
One method for initially bonding the mirror mounting bracket to the windshield uses a heat curable organic or organosilicon adhesive. To achieve maximum bonding strength between the glass and the metal bracket the mating surfaces should be pressed together while the mounting bracket is heated to accelerate curing of the adhesive. This operation is typically carried out by placing the windshield in an oven, which is relative easy when the windshield has not yet been assembled on to the frame of a vehicle.
Applying the required combination of heat and pressure to the internal surface of the windshield of a vehicle while maintaining the position of the mounting bracket and doing this in the relatively confined space available in the front seat of a vehicle presents a number of logistical problems that cannot be adequately solved using available equipment.
One objective of the present invention is to provide a tool, referred to herein as a reworking tool, that will provide the combination of heat and pressure required to adhesively bond a mirror mounting bracket to an automotive windshield yet is sufficiently small and portable to be used in the interior of an assembled vehicle.